[Gene pool of ethnic groups of the caucasus: results of integrated study of the Y chromosome and mitochondrial DNA and genome-wide data].

Genetic diversity has been analyzed in 22 ethnic groups of the Caucasus on the basis of data on Y-chromosome and mitochondrial DNA (mtDNA) markers, as well as genome-wide data on autosomal single-nucleotide polymorphisms (SNPs). It has been found that the West Asian component is prevailing in all ethnic groups studied except for Nogays. This Near Eastern ancestral component has proved to be characteristic of Caucasian populations and almost entirely absent in their northern neighbors inhabiting the Eastern European Plain. Turkic-speaking populations, except Nogays, did not exhibit an increased proportion of Eastern Eurasian mtDNA or Y-chromosome haplogroups compared to some Abkhaz-Adyghe populations (Adygs and Kabardians). Genome-wide SNP analysis has also shown substantial differences of Nogays from all other Caucasian populations studied. However, the characteristic difference of Nogays from other populations of the Caucasus seems somewhat ambiguous in terms of the R1a1a-M17(M198) and R1b1b1-M73 haplogroups of the Y chromosome. The state of these haplogroups in Turkic-speaking populations of the Caucasus requires further study.

[Analysis of Alu-insertion polymorphism in three subethnic groups of Kalmyks].

Eight Alu insertions at the NBC27, TPA25, NBC148, NBC123, ACE, APOA1, NBC51, and PV92 locus were examined in three subethnic groups of Kalmyks (Torgouds, Derbets, and Buzava). In general, the pattern of allele frequencies in Kalmyks was consistent with that in Asian populations of the world, and was similar to the Alu insertion frequencies pattern in Turkic populations of the Volga--Ural region and Central Asia. Pairwise comparisons of three subpopulations of Kalmyks with respect to the frequency distributions of eight Alu insertions revealed the differences between the groups examined. The coefficient of gene differentiation, F(st), constituted 1.37%, pointing to the common origin of the groups of interest, as well as to the uniformity of the gene pools of subethnic groups of Kalmyks examined.

[The role of angiotensin-converting enzyme and apolipoprotein E in the development of intracranial aneurysms.].

The distribution of allele and genotype frequencies of the Alu-insertion polymorphism of the angiotensin-converting enzyme (ACE) gene and missence mutations leading to the substitution of arginine to cysteine in positions 112 and 158 of apolipoprotein E (APOE) has been studied in 166 patients with brain intracranial aneurysms and in 192 controls of Russian origin from Ural region. Brain vascular aneurysms with hypertension were associated with the D*D* ACE genotype in men and with the e2 allele and the e2/e3 APOE genotype in women. The association was also observed between the e2 allele and the e2/e3 APOE genotype and family history of stroke, hemorrhages and aneurysms in patients. Men with the I*D* ACE genotype and the e4 APOE allele were at lower risk.

[The analysis of the SpI (1546G>T) polymorphism of the Col1A1 gene and the FokI (3663T>C) polymorphism of the vitamin D receptor gene in patients with syringomyelia].

The SpI (1546G>T) polymorphism of the CollA1 gene and the FokI (3663T>C) polymorphism of the vitamin D receptor gene have been studied in patients with syringomyelia and controls of different ethnic origin (Tartars, Bashkirs, Russians). Ethnic differences in allele and genotype frequencies have been revealed in the control group. Frequency of the s allele of the CollA1 gene was higher in Russian patients and that of the FokI FF genotype in Tartar patients. The data obtained suggest a possible role of these genes in the pathogenesis of syringomyelia.

[AFBN1 gene in patients with Marfan syndrome].

30 exons have been analyzed using SSCP in patients with MFS or related phenotypes. We report 2 missense mutations occur in calcium-binding Epidermal Growth Factor-like (EGFcb) domains and 9 polymorphisms located both in coding and noncoding regions of FBN1 gene. Three intragenic microsatellite polymorphic markers MTS-1, MTS-2 and MTS-4 have been analyzed in patients with MFS and unrelated unaffected control individuals. We found significant differences in allele frequency distribution of MTS-2 and MTS-4 loci between MFS patients and unaffected individuals. Haplotype frequency distribution on normal and mutant chromosomes were significantly different. The most common haplotype was 2-11-8 which was predominant on normal chromosomes of affected individuals. Haplotype 2-2-8 was observed in 18% of cases on mutant chromosomes and in 4% of cases on normal chromosomes. These data demonstrate possibility and application of haplotype-segregation analysis with use of these intragenic markers for diagnostic purposes in affected families by Marfan's syndrome.

[Analysis of ethnogeographic groups of Kazakhs based on nuclear genome DNA polymorphism].

Eight nuclear DNA loci, including six Alu insertions (ACE, APOA1, PV92, TPA25, Ya5NBC27, and Ya5NBC148), 32-bp deletion in the CCR5 gene, and VNTR locus at the eNOS gene, were examined in three ethnogeographic groups of Kazakhs (342 individuals). The individuals examined lived in southeastern, central, and southwestern regions of Kazakhstan, and according to their tribal attribution, belonged to the Senior, Middle, and Junior Zhuzes. The Alu insertions appeared to be polymorphic in all populations examined: the insertion frequency varied from 0.264 in the populations of the Senior and Middle Zhuzes at the Ya5NBC27 and Ya5NBC148 loci, to 0.827 in Kazakhs of the Middle Zhuz at the APOA1 locus. In Kazakh groups examined only two alleles of the eNOS VNTR locus were detected with the number of repeats constituting four (A) and five (B) copies. The highest frequency of A allele was found in Kazakhs from the Junior Zhuz (0.113), while the highest frequency of B allele was detected in population of the Senior Zhuz (0.893). The frequency of the 32-bp deletion in the chemokine receptor CCR5 gene varied from 0.027 in the Junior Zhuz to 0.045 in the Senior Zhuz. Kazakhs showed high genetic diversity (Hex = 0.376). In general, in three ethnogeographic groups of Kazakhs, the coefficient of gene differentiation (G(ST)) over eight diallelic markers of nuclear genome constituted 1.1%. The differences in the Alu insertions made the highest contribution to the among-population diversity (G(ST) = 1.2%).

[Polymorphism of CTG-repeats in the DMPK gene in populations of Yakutia and central Asia].

Allele frequency distribution of CTG-repeat in the 3'-flanking region of DMPK gene was analyzed in populations of Yakutia (three ethnogeographical groups of Yakuts, Evenks, Evens, Yukaghirs, Dolgans) and Central Asia (Kazakhs, Uzbeks, Uighurs). Frequencies of CTG alleles were found to be significantly different in two regions. Allele frequency distribution in populations of Yakutia was similar to Asian populations, whereas Central Asian populations showed similarity to European populations. The features of allele spectrum in Yakut populations were discussed in terms of high prevalence of myotonic dystrophy in Yakuts. Our result supports the hypothesis of founder effect in spread of myotonic dystrophy in Yakuts. The phylogenetic relationships between the investigated populations based on polymorphism of CTG-locus of the DMPK gene have been analyzed as well.

[Analysis of mitochondrial DNA variation in the population of Oroks].

Mitochondrial DNA (mtDNA) variation was studied in population of Oroks (n = 61), the indigenous inhabitants of Eastern Siberia. Most of the mtDNA types examined fell into five haplogroups (C, D, G, M10, and Y) typical of Eastern Eurasian populations. For three haplogroups (D, C, and M10), the founder effect was established. In one individual, a unique lineage belonging to haplogroup HV and typical of Caucasoids was detected.

[Phylogeografic analysis of mitochondrial DNA Nogays: the high level of mixture of maternal lineages from Eastern and Western Eurasia]. / Filogeograficheskii analiz mtDNK nogaitsev: vysokii uroven' smesheniia materinskikh linii vostochnoi i zapadnoi Evrazii.

Analysis of markers mtDNA in a population of Nogays (n = 206), living on Nothern Caucasus and speaking on language of Turkic branch of the Altaic linguistic family, has shown, that the level of their genetic differentiation is high (H = 0.99). Among the found haplotypes there is all the basic Western Eurasian haplogroups, most often of which are clusters H (22%) and U (21%), however, the percentage of the lineages specific only for populations of East Eurasia (40%) is highest. In a population of Nogays there are also variants mtDNA, belonging to haplogroup M1, characteristic for North East Africa, and gaplogroup U2, typical for populations of India. This testifies about presence in a gene pool of Nogays people of components of a various parentage.

[Genetic structure of people from the Volga-Ural region and Central Asia from data of Alu-polymorphism]. / Geneticheskaia struktura narodov volgo-ural'skogo regiona i srednei azii po dannym Alu-polimorfizma.

Nine Alu loci (Ya5NBC5, Ya5NBC27, Ya5NBC148, Ya5NBC182, YA5NBC361, ACE, ApoA1, PV92, TPA25) were analyzed in six ethnic populations (Trans-Ural Bashkirs, Tatars-Mishars, Mordovians-Moksha, Mountain Maris, Udmurts, and Komi-Permyaks) of the Volga-Ural region and in three Central Asian populations (Uzbeks, Kazakhs, and Uigurs). All Alu insertions analyzed appeared to be polymorphic in all populations examined. The frequency of insertion varied from 0.110 in Mountain Maris at the Ya5NBC5 locus to 0.914 in Tatars at the ApoA1 locus. The data on the allele frequency distribution at nine loci point to the existence of substantial genetic diversity in the populations examined. The value of the observed heterozygosity averaged over nine Alu insertions varied from 0.326 in Mountain Maris to 0.445 in Kazakhs and Uigurs. The level of the interpopulation genetic differences for the Volga-Ural population (Fst = 0.061) was higher than for the populations of Central Asia (Fst = 0.024), Europe (Fst = 0.02), and Southeastern Asia (Fst = 0.018). The populations examined were highly differentiated both in respect of linguistic characteristics and the geographical position. The data obtained confirmed the effectiveness of the marker system used for the assessment of genetic differentiation and the relationships between the ethnic groups.

[VNTR-polymorphism of the PAH, e-NOS genes and deletion of the CCR5 gene in populations in the northern Caucasus]. / Izuchenie VNTR-polimorfizma genov RAN, eNOS i deletsii gena CCR5 u narodov severnogo Kavkaza.

VNTR allelic polymorphism at the phenylalanine hydroxilase (PAH) and endothelial constitutive nitric oxide synthase (eNOS) genes and the prevalence of the CCR5 chemokine receptor gene 32-bp deletion were examined in four indigenous populations of Northern Caucasus, Adygs, Kumyks, Karachais, and Nogais (Kuban and Karanogais). Population-specific features of the allele and genotype frequency distribution patterns of the polymorphisms examined were described. The data obtained were compared to those obtained from literature. The results of the study confirmed that the frequency and occurrence of the PAH polymorphic alleles exhibit substantial interpopulation differences. In the populations of Northern Caucasus, the eNOS minisatellite polymorphism alleles and genotypes frequency distribution patterns were close to those described earlier for populations of the Volga-Ural region (VUR), and also for the Australian Caucasoids, Japanese, and Turks. In the populations examined, the mean frequency of the CCR5 gene deletion was 0.055, which was somewhat lower than in the populations of VUR (0.07) and Europe (0.081), and practically identical to that in Asian populations (0.050). For each population observed and expected heterozygosities at each locus were calculated. In general, the gene pool of Northern Caucasian populations showed substantial differentiation at the loci examined: the GST value was 0.0274. The data for individual loci showed that the greater contribution to the interpopulation diversity was made by the differences in the PAH VNTR allele frequencies (GST = 0.04), while the differences at the eNOS and CCR5 loci were small (GST = 0.0025 and GST = 0.0039, respectively).

[Analysis of polymorphic loci of Huntington genes in peoples from the Volga-Ural region]. / Analiz polimorfnykh lokusov gena khori gentington u narodov volgo-ural'skogo regiona.

Eleven populations of the Volga-Ural region were analyzed with respect to three intragenic polymorphisms of the Huntington disease gene (IT15), including highly polymorphic (CAG)n and moderately polymorphic (CCG)n of exon 1 and neutral del2642 of exon 58. In the case of (CAG)n, 101 genotypes were observed, with genotype number varying from 15 in Southeastern Bashkirs to 34 in Mari. Allele diversity RS ranged from 9.70 in Southeastern Bashkirs to 18.00 in Chuvash, averaging 13.79 +/- 2.12. The (CAG)n allele frequency distribution was unimodal and had a maximum at (CAG)17. In the case of (CCG)n, six alleles with 6-10 or 12 repeats were observed. RS was 4.13 +/- 0.44, ranging from 3.73 in Udmurts to 4.99 in Tatars. In the case of del2642, allele del- was detected at a frequency 0.830 in Mari to 0.932 in Udmurts. Of all Volga-Ural ethnic populations, Finno-Ugric ones proved to be most heterogeneous with respect to the three polymorphisms, whereas Turkic populations and, in particular, Bashkirs were homogeneous. Micro-differentiation of the Volga-Ural populations corresponded to the European type.